#ifndef DIRECT_H
#define DIRECT_H

#include <math.h>
#include <stdio.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

typedef double (*direct_objective_func)(int n, const double *x,
                                        int *undefined_flag, void *data);

typedef enum { DIRECT_ORIGINAL, DIRECT_GABLONSKY } direct_algorithm;

typedef enum {
  DIRECT_INVALID_BOUNDS = -1,
  DIRECT_MAXFEVAL_TOOBIG = -2,
  DIRECT_INIT_FAILED = -3,
  DIRECT_SAMPLEPOINTS_FAILED = -4,
  DIRECT_SAMPLE_FAILED = -5,
  DIRECT_MAXFEVAL_EXCEEDED = 1,
  DIRECT_MAXITER_EXCEEDED = 2,
  DIRECT_GLOBAL_FOUND = 3,
  DIRECT_VOLTOL = 4,
  DIRECT_SIGMATOL = 5,
  DIRECT_MAXTIME_EXCEEDED = 6,

  DIRECT_OUT_OF_MEMORY = -100,
  DIRECT_INVALID_ARGS = -101,
  DIRECT_FORCED_STOP = -102
} direct_return_code;

#define DIRECT_UNKNOWN_FGLOBAL (-HUGE_VAL)
#define DIRECT_UNKNOWN_FGLOBAL_RELTOL (0.0)

extern direct_return_code
direct_optimize(direct_objective_func f, void *f_data, int dimension,
                const double *lower_bounds, const double *upper_bounds,

                double *x, double *minf,

                int max_feval, int max_iter, double start, double maxtime,
                double magic_eps, double magic_eps_abs, double volume_reltol,
                double sigma_reltol, int *force_stop,

                double fglobal, double fglobal_reltol,

                FILE *logfile, direct_algorithm algorithm);

#ifdef __cplusplus
} /* extern "C" */
#endif /* __cplusplus */

#endif /* DIRECT_H */
